This invention relates to a sulfur-reactive contact material for removing sulfur-containing impurities from a refined hydrocarbon feed. More particularly it relates to removing such impurities by contacting the feed with a novel material containing a sulfur-reactive agent and having a pore volume of at least 0.15 cc per cc of which 5% is in pores having a diameter in the range 0.1 to 15 microns.
In the refining of crude oil, product streams are obtained which contain a relatively minor amount of sulfur-containing impurities, for example thiols, thiophenes, hydrogen sulfide, organic sulfides, sulfur-containing heterocyclic organic compounds and the like. Such impurities reduce the desirability of a stream for many uses and may even make it unacceptable, for example as a feed to a naphtha reformer unit and the like. Contemporary anti-pollution standards greatly limit the amount of sulfur which may be present in any form in hydrocarbon fuels.
It is known to reduce the sulfur content of a refined hydrocarbon by contacting it with a material comprising a sulfur-reactive agent such as one comprising copper, iron, zinc and compounds thereof, especially where these materials are disposed upon an inert carrier material (see for example U.S. Pat. Nos. 2,755,226; 2,769,764; 3,192,152; 3,382,044; 3,441,370; and 3,660,276). A serious limitation of these materials is that the desired sulfur-removing reactions resulting from the contacting of the feed with the material are subject to diffusion limitations. In order to make a more effective use of the contact material in such a case, it is necessary to reduce the space velocity of the feed. This is disadvantageous because it lowers the capacity of the process unit involved.